For the Architects: Greens Slopes

[Steve Okula]

I'm in the process of remodeling a green. What is the range of degrees of slope that you use for pinnable positions?

I'm sure this has been discussed in the past, but I'm too busy to go search it. (Wait, "busy" is not the right word. How about "lazy"?)

[Tom_Doak]

Steve:

My standard is generally 3% or less.  But, if you really know your stuff, it depends on the situation.  You can get away with something steeper in a small part of the green, if it gets flatter below that ... but you don't want to push the limits at the front or the edges of the green, where if the greens get quick, people will be putting off the green all day.

A few guys set the bar at 2% -- and generally, their greens are either boring or manufactured in appearance.

MacKenzie and Maxwell generally used 4.5% back in the day, based on shooting grades on their greens, although Press Maxwell told Jim Urbina they never surveyed their greens and just did it all by eye.  The advantage of using a steeper standard is that you can keep greens on hilly ground as a flowing surface, without having to resort to multiple tiers.

It also matters a bit if you are in a windy place; if so you have to err on the side of caution, either with contouring or with green speeds.

[Mike Nuzzo]

Are you building it yourself?
Why not have someone help you with some ideas or details -- you never know what they might add?
Don't you have other work to tend to?
cheers

[Neal_Meagher]

Tom,

I agree that in general terms 1.5% to 3.0% max is the norm for pinnable areas, but there seems to be wild variations in transition slopes within greens.  For instance, I know you are very familiar with Pasatiempo - I had the opportunity to put a smart tool to the 16th green once and I got some crazy slopes toward the front of that one in the range of 12% - 16%.  I'm curious if you, or any other architects on here, have any rules of thumb you use for these areas.

[Bill_McBride]

Tom,

I agree that in general terms 1.5% to 3.0% max is the norm for pinnable areas, but there seems to be wild variations in transition slopes within greens.  For instance, I know you are very familiar with Pasatiempo - I had the opportunity to put a smart tool to the 16th green once and I got some crazy slopes toward the front of that one in the range of 12% - 16%.  I'm curious if you, or any other architects on here, have any rules of thumb you use for these areas.

Neal, I remember you measuring the slope at the front of #8 at Pasatiempo -- wasn't it 6% down there? 

[Neal_Meagher]

Panhandle Bill,

You remember that day.......well there were some 6% slopes in many places but what sticks in my mind was the very steep slope toward the front.  Now, that was a few years ago and maybe my memory is going, but that's what I remember.  Perhaps Tom can chime in and verify that.  Either that that green IS that steep in a spot or two or that my memory is going....one or the other.

[Jeff_Mingay]

MacKenzie and Maxwell generally used 4.5% back in the day, based on shooting grades on their greens, although Press Maxwell told Jim Urbina they never surveyed their greens and just did it all by eye. 

It's very interesting (to me) that Mackenzie and Maxwell never surveryed their greens. Very interesting.

Working with Rod Whitman the past 10 years, we've also done a lot of "eyeballing", but certainly do survey as well. 2-3% is usually the aim in pinnable areas. However, like Tom D., Rod's always professing you can get away with more in certain situations... and, we have!

[Tim Nugent]

The problem with Rules of Thumb is there is always an exception and an interpertation.  Internal slopes in greens depend on many variables - some of which were previously touched upon.  Tom's 2-3% is probably a good starting point but this is for the "Pinnable" areas.  Not the perimeter 9-12' (depending on how close you pin to the edge and the collar width) or internal transitions.  A lower area coming off a 3' transition, you might want flatter than one coming off an 18" one.  I think many experienced guys can Eyeball greens because the can figure the play of the ball.  Also the size of the green, how much the green is partitioned or sectioned, and the expected speed of the green have to be factored in the mix.

I think one of the reasons for flatter greens to get boring is that greens tend to get flattened-out at each level of construction - especially the pea gravel level.  Many subtile contours can simply "get lost".  Best to be a bit over-zealous in the subgrade to anticipate this.

Neal 8-12% - but there are always exceptions   With shorter and shorter cutting heights, the top and bottoms of the those transitions are getting trickier and trickier to allow for a uniform cut - especially on an angle.

[Jeff_Brauer]

Steve,

I'm with Mike N, get some help. Oh,wait, you are getting architectural help and getting it free, too!

I will only chime in that you need to either measure the truly down hill slope at 3% or use the USGA and Masters method of putting a digital level two different ways on the finished slope in the cuppable area and average those two slopes.  If I design a swale that drops 3%, but it also has a cross slope (as it does except in the very bottom) then the total slope of any pin position is greater than 3%.

In general, your downhill swale grade ought to be 2-2.25% max to account for this.

BTW, years ago TePaul proposed the simplest way for an existing club to figure this out - go put the level on a green area/pin position that members think is the max slope, meaure it, and then recreated it on the new green.....

[Steve Okula]

Are you building it yourself?
Why not have someone help you with some ideas or details -- you never know what they might add?
Don't you have other work to tend to?
cheers

Mike,

To answer your questions: Yes, yes, and yes.

Yes, I'm building it myself, and I won't have it any other way. It's the only fun I get on my job.

And yes, as Jeff so perceptively points out, the fact that I'm posting here, picking the finest minds in the golf design community, means I am getting people to help, and without paying a commision.

And yes, I do have lots of other work to do, but see my answer to your first question.

Cheers right back at ya.

[Mike Nuzzo]

Thank you Steve
Have fun
It is helpful to know as I try to help supers all the time

Why not go all out
Post some pics and a sketch
I was inferring having someone else look at it because you never know what they will see - maybe off the surface that ties back in...
I brought someone to a proposal recently and they suggested something that I didn't consider because I knew it was off limits...
It was a good enough idea to try and push to make it within limits.

And I measure slopes using a digital level - rotate it until you get the greatest value - that is the slope no mater what Augusta or or JB say. 

[Tom_Doak]

And I measure slopes using a digital level - rotate it until you get the greatest value - that is the slope no mater what Augusta or or JB say. 

Yes, Mike, when I talk of 3% I am talking about measuring the fall line of the green ... not just front-to-back or side-to-side, but the maximum slope.  Sometimes my associates / shapers just measure back-to-front, so I've got to keep them honest.

Neal:

Your memory is probably correct.  I don't remember exact numbers for the 8th at Pasatiempo ... but, since the green gathers to the middle, you are seldom forced to putt right down the fall line ... you can putt off a bank to one side or the other, which makes it less severe.

I have measured or seen topo maps for many famous greens which have slopes of 6% in pinnable areas.  The second green at Pine Valley is nearly ALL greater than 4%.  The Redan at National falls 6% toward the back left at the entrance, "flattens out" to 4% in the middle of the green, and then goes off the back at 6% !!

[Jeff_Brauer]

Mike N,

Re read my post and see if that answer was really necessary....I said to read the true downhill grade or take the average.  Perhaps I should have said max downhill grade for you to understand it.....smiley face or not.

[JC Urbina]

Neal,

When I did the greens expansions a few years back I surveyed the 8th green.

 The back 1/4 of the green is 2/3 percent.

The middle checks in at 4 -6 percent

The front is at 8 percent with some  (flat spots- ha)  in the gradient.

[Brian Phillips]

We stick to about max 3% on Creeping Bent greens but use 4%-5% on some of our Bent Fescue greens depending on mowing budgets and mowing heights.